The difference between the PBX and the group telephone system is that the users of the group telephone system need manual operation to dial the external line, while the PBX automatically completes this task. The hybrid system includes the functions of the above two systems.

For some telephone exchanges, a strictly defined classification cannot be unified. Due to the different names of manufacturers, customs, regions, product positioning and other factors. So you don't need to pursue it too deliberately, just purchase the appropriate equipment according to your own use requirements.